Could the events of more than four hundred years ago really have some bearing on the murder of a brilliant history student? When a long lost journal, written by an Irish General in the seventeenth century, arrives at the university, apparently sent by the student before he died, Professors Latimer and Reilly know they must investigate – not least to quell accusations that the student was involved with illegal drugs and, somehow, the university is responsible.

Although the words in the journal are in code, the student has included the key to the cipher. It remains a long, tedious task to unravel the full, unbelievable story. Meanwhile, the two professors' investigations are drawing them deeper and deeper into a world of witches and the occult, that seems to centre on a tiny Irish town where the violent, unnatural happenings of 1689 have never been fully resolved...